Sheet material fastening tool



March 9, 1943- J. J. DOMONKOS 2,313,228

- SHEET MATERIAL FASTENING TOOL Filed Oct. 7, ;940

ATTORNEYS Patented Mar. 9, 1943 UNITED. STATES ATENT OFFICE SHEET MATERIAL FASTENING TOOL Julius J. Domonkos, Kenmore, N. Y., assignor to Bell Aircraft Corporation, Buffalo, N. Y.

3 Claims.

This invention relates to methods and means for fastening wing covering sheet material to supporting frame structure. One of the objects of the invention is to provide a simplified and improved method for fastening sheet material, such as fabric or the like, to former elements of aircraft structures. Another object of the invention is to provide an improved tool for carrying out the novel method thereof. Other objects and advantages of the invention will appear in the following specification.

In the drawing:

Fig. 1 is an end elevation of a tool of the invention;

Fig. 2 isa side elevation thereof;

Fig. 3 is a diagrammatic view illustrating one phase of the method of the invention as performed by one portion of the tool of Figs. 1 and 2;

Fig. 4 is a view similar to Fig. 3 showing operation of another portion of the tool of Figs. 1 and 2;

Fig. 5 is a view similar to Fig. 3 showing operation of another portion of the tool of Figs. 1 and 2;

Fig. 6 is a view similar to Fig. 3 showing operation of another portion of the tool of Figs. 1 and 2;

Fig. 7 is a fragmentary view in side elevation, with portions broken away, of another form of the tool of the invention; and

Fig. 8 is a bottom plan View of the tool of Fig. 7.

The invention is illustrated herein as being employed in connection with the mounting of fabric covering material upon a rib element of an airplane structure; the rib element being generally of T-shaped sectional form and designated generally by the numeral I0. A covering fastening plate i2 is illustrated sectionally in Figs. 3, 4, 5 and 6 throughout the various stages of its adjustment into finally mounted form upon the rib member Hi. The fabric covering sheet is designated by the numeral M. The cap strip portion of the rib member ID is centrally grooved at its outer face and provided with lateral recesses I6 at opposite sides of the grooved portion.

To mount the covering l4 upon the rib ill in locked relation thereon in accord with the method of the invention, the covering sheet I4 is disposed against the outer face of the cap strip portion of the rib member, and the locking plate [2 is then pressed against the outer face of the covering sheet and into the recessed portion of the rib member as illustrated in Fig. 3; the locking plate 12 having been previously bent to the sectional form illustrated in Fig. 3. Particular attention is called to the fact that the locking plate 12' has also been previously bent inwardly at its opposite side portions so as to form fixed abutments is at the underside thereof adjacent each longitudinal edge. A tool such as that illustrated in Figs. 1 and 2 is then brought into play upon the locking plate I2 so as to permanently fasten it into covering locking engagement with the rib member l0. To this end the tool is illustrated as comprising generally a U-shaped frame portion upon which are mounted a succession of rollers 22, 24, 26 and 28 by means of pins 29. The frame member is also provided with a U- shaped bracket supporting at itsupper end a inperipheral form.

. Thus, as the tool is rolled along the locking plate 12 in a direction corresponding to movement of the tool from right to left as viewed in Fig. 2, the rollers of the tool will successively iron the locking plate 12 downwardly to generally flat.

sectional form and in such manner that the longitudina'l side edge portions of the lockingplate are projected into the recesses It at opposite sides of the rib member. Particular attention is called, however, to the fact that the roller 24 coacts with the fixed abutment portions 18 of the looking plate to give the locking plate a reversely bent sectional form as illustrated in Fig. 4. Consequently, upon subsequent contact with the flat surfaced rollers 26 and 28 the intermediate body portion of the locking plate I2 is depressed to the final position illustrated in Fig. 6 in such manner that the locking plate is generally bowed downwardly throughout its center section and is in contact at its middle with the upper face of the rib member 10. Consequently, upon removal of the tool from operative position, the locking plate I2 is adapted to remain in the condition illustrated in Fig. 6 because the oppositely directed tension forces in the fabric M at. opposite sides of the rib member are converted into compression forces at opposite side portions of the locking plate 12 which tend to'bow it further downward- 1y, as distinguished from upwardly in such manner as would cause the locking plate to spring out of engagement with the rib member. Hence, when mounted in the final position of Fig. 6, the locking plate 12 is stable and provides positive protection against accidental displacement of the covering fastening device. It will be understood, however, that the locking plate l2 may be made of relatively soft metal sheet, or the like, whereby it may subsequently be upset, as by insertion of a screw driver or some such similar tool between the locking plate and the rib member Ill so that the locking plate may thereby be pried upwardly and out of the groove of the rib, as for repairor replacement purposes.

As illustrated in Figs. 7 and 8, the tool of the invention may be provided in the form of a single shoe 40 having its lower face so dimensioned as to fit the groove within the cap strip portion of the rib member It. The shoe is mounted upon the lower end of a stem 42, the upper end of which is telescopically engaged within a tubular handle portion 44. The upper end of the stem 42 is provided with a hardened head 46, and the handle 44 may be provided with inwardly extending shoulder portions 48 to retain the stem 42 within the handle against accidental disassembly therefrom. A reciprocal piston 59 is mounted within the tubular handle 44 so as to be adapted to operate in the manner of ahammer against the head it, and it will be understood that the piston will be arranged to be reciprocated in response to fluid pressure forces or electromagnetic forces, or the'like, suitably controlled from externally of the tool.

As illustrated in Fig. 8, the shoe 40 is grooved in its lower face portion as indicated at 52; the groove 52 being of tapering form and a decreasing depth from the forward end of the shoe and running out at a point slightly aft of the longitudinal center thereof. Thus, the rear end of the shoe 48 is of fiat undersurface form; and it will be understood that the shoe 40 is thereby adapted to function as an ironing tool against the bowed locking plate of Fig. 3 so as to deform it through the sectional positions illustratedby Figs. 4 and 5 and into the final sectional form illustrated and described hereinabove in connection with Fig. 6. Thus, the tools of Figs. 1-2 and Figs. 7-8 are adapted to be manually pressed and moved longitudinally against the locking plat l2 for the purpose described, and in order to reduce somewhat the pressure forces necessarily applied thereon by the operator of the tool, the hammer mechanism 50 of Fig. 7 may be caused to operate simultaneously with the longitudinal movement of the tool relative to the locking plate.

Although only a limited, number of forms of the invention have been shown and described in detail, it will be apparent to those skilled in the art that the invention is not so limited but that various changes may be made therein without departing from the spirit of the invention or the scope of the appended claims. w

Iclaim:

1. A hand tool comprising a frame and a plurality of rollers rotatably mounted upon said frame upon spaced parallel axes and in peripheral alignment, the roller at one end of said element being relatively deeply grooved in its peripheral face, the roller at the other end of said alignment being of flat section-a1 contour at its peripheral face, and the other of said rollers being grooved to varying depths to provide substantially uniform gradationbetween the sectional peripheral face contours of said end rollers.

2. A hand tool for assembling a locking element of sheet metal form originally bowed into arcuate transverse sectional form by progressively flattening said element to project its opposite longitudinal edges into assembled position; said tool comprising a frame and a locking-elementsurface contacting means supported thereby and adapted to be moved longitudinally of said element, said contacting means having a leading surface portion of substantially concave contour to seat over the original convex surface of said element to be centered thereby and successive surface portions varying from grooved to flat sectional contour, said successive portions being in the form of aligned rollers.

3. A hand tool comprising an elongate channeled holder, handle means secured to the web thereof, and a plurality of aligned rollers rotatably supported between the flanges of said channel and having peripheral portions projecting therefrom, the periphery of the roller at one end of said holder being of relatively con-cave cross sectional contour and the periphery of the roller at the other end of said holder being of relatively flat cross sectional contour, the intermediate rollers being of peripheral cross sectional contours grading progressively between said concave periphery and said flat periphery.

JULIUS J. DOMONKOS. 

